I'd have to ask what type of designers are the target - professionals or crafters who are doing it for fun and not necessarily for selling. Images of finished products and links to directions on how to make the products might be useful. List 10 products/projects and then write 10 pages for each project and link all back to each other for example. It might be a small but good start. Feature projects/products of the month, maybe have some contests and give away a few supplies. I've just started with contests on my site and I have found the traffic increased as well as the time people are spending at the site. One thing I did was to have people vote for the best - this has brought in alot of visitors that have come to vote for their friend's item and then they end up staying and bookmarking/subscribing to my site. Just some quick thoughts.